What Does an EBOO Filter Do? PES H200 Membranes Explained

A technical explanation of the EBOO PES H200 filter module: hollow-fiber polyethersulfone construction, high-flux dialyzer nomenclature, the fluid path through the module, and why it is single-use.

What an EBOO Filter Actually Is

An EBOO filter is a hollow-fiber polyethersulfone (PES) membrane module — the same class of component the dialysis industry calls a high-flux dialyzer. In an EBOO research circuit it is the single-use separation element the fluid path runs through. This guide explains the construction, what the "H200" designation denotes, how fluid moves through the module in a research circuit, why the part is single-use, and how to verify compatibility before ordering.

Everything below describes equipment and fluid mechanics. It makes no claim about what the module does to human blood in any clinical context. The filters sold here are supplied for laboratory and research use only. They are not medical devices and are not cleared or approved by the U.S. FDA for clinical, diagnostic, or therapeutic use.

Construction: Hollow Fibers in a Potted Shell

Open a cutaway of a hollow-fiber module and you find thousands of narrow polymer capillaries bundled inside a rigid cylindrical housing. Each end of the bundle is "potted" — sealed into a resin block — so that the inside of the fibers (the lumen side) and the space around them (the shell side) form two separate compartments with their own ports.

That geometry is the entire point. A few thousand fibers a couple of hundred microns across pack an extremely large membrane surface area into a module small enough to clamp onto a benchtop device, and they do it while keeping the pressure drop across the module low enough for a modest pump to sustain flow.

Why polyethersulfone? PES is the workhorse membrane polymer for this application because it combines three properties that are hard to get together: thermal and chemical stability, a controllable pore-size distribution during spinning, and low non-specific protein binding relative to older cellulose-derived membranes. It also tolerates the sterilization methods used for single-use disposables.

What "H200 High-Flux" Denotes

The nomenclature comes from dialyzer convention rather than from EBOO specifically.

• "High-flux" describes membrane permeability. In dialyzer classification, high-flux membranes have larger, more open pores and a substantially higher ultrafiltration coefficient than low-flux membranes, so fluid and mid-sized solutes move across the membrane more readily at a given transmembrane pressure. It is a permeability class, not a brand.
• "H200" is the module designation within that class, identifying the specific membrane and housing configuration — effective surface area, fiber geometry, and port arrangement — used in EBOO circuits.

For procurement purposes, treat "PES H200 high-flux" as the full specification string. Writing only "filter" or only "H200" on a requisition is the most common cause of an incompatible substitution arriving on the loading dock.

The Fluid Path Through the Module

In a closed-loop EBOO research circuit the module is one stage in a continuous loop:

1. The peristaltic pump section draws fluid from the line set at circuit flow — 2.5 to 5 L/hr on the EBOO O3 Research Device 2026.
2. Fluid enters the module at the inlet port and distributes into the fiber lumens across the potted header.
3. It travels the length of the fibers. Along that path, exchange occurs across the membrane wall between the lumen side and the shell side, governed by the pressure differential and the membrane's permeability class.
4. Fluid recombines at the outlet header and leaves through the outlet port, continuing to the next stage of the circuit — including, on cuvette-equipped line sets, the integrated UV chamber.
5. The loop returns through the remainder of the line set.

Two operational points follow. Orientation matters: modules have a defined inlet and outlet, and reversing them changes the flow distribution across the bundle. Priming matters: air trapped in fiber lumens takes those fibers out of service for the entire run, which is why priming procedure is part of the standard pre-run check rather than an optional step.

Why the Module Is Single-Use

Single-use is a data-integrity requirement before it is anything else.

• Fiber patency changes with use. Protein layering and partial fiber occlusion alter effective surface area during a run. A reused module starts the next run from an unknown baseline.
• Membrane properties drift. Permeability after exposure and cleaning is not the permeability on the datasheet, so the specification you cite in a methods section no longer describes the part you ran.
• Cross-contamination. Any carryover between runs is an uncontrolled variable.
• Integrity is not verifiable at the bench. There is no practical benchtop test that confirms fiber integrity across the whole bundle after a run.

Standard protocol is one module per run.

Verifying Compatibility Before You Order

Confirm four things before a filter order goes out:

1. Connector geometry. EBOO line sets use luer-lock connections. Verify the connector standard on both the module and your existing tubing rather than assuming.
2. Module specification. PES H200 high-flux — the full string, on the purchase order.
3. Whether you need a filter alone or a complete set. The single PES H200 replacement filter suits labs that already stock tubing. The Filters & Lines Complete Kit supplies tubing, line set, and filter together for a full run.
4. Pack size against run cadence. Kits ship in 10-packs; single filters are sold individually for gap coverage.

Full specifications and stock for every option are on the EBOO filters category page, and line-set choices are compared on the lines and tubing page. If you are unsure whether a filter fits your existing circuit, a free compatibility review is faster than returning an incompatible part — all sales are final.

All products described are for laboratory and research use only. Not cleared or approved by the U.S. FDA for clinical, diagnostic, or therapeutic applications.

Frequently Asked Questions

What does an EBOO filter do in a research circuit?

It is the single-use hollow-fiber separation module in the closed loop. Fluid enters the module, distributes into thousands of polyethersulfone capillaries, exchanges across the membrane wall according to the membrane's permeability class, and exits through the outlet port to the next circuit stage.

What does PES H200 high-flux mean?

PES is polyethersulfone, the membrane polymer. High-flux is a dialyzer permeability class denoting larger pores and a higher ultrafiltration coefficient than low-flux membranes. H200 identifies the specific module configuration — membrane, surface area, and housing — used in EBOO circuits.

Can EBOO filters be reused?

Standard research protocol is one filter per run. Fiber patency and membrane permeability change during use, bundle integrity cannot be verified at the bench afterward, and reuse introduces carryover — all of which undermine run-to-run comparability.

How do I know a filter fits my device?

Check three things: luer-lock connector geometry, the full PES H200 high-flux specification, and whether your line set already includes a filter. Request a compatibility review before ordering if any of the three is uncertain.

References

• Di Paolo N, Bocci V, Gaggiotti E. "Ozone therapy." The International Journal of Artificial Organs, 2005 (describes the extracorporeal circuit and filter module context): https://pubmed.ncbi.nlm.nih.gov/15818542/
• U.S. Food & Drug Administration, "Research Use Only" labeling guidance: https://www.fda.gov/regulatory-information/search-fda-guidance-documents